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    <script>
        /* 
           数组去重 ['blue', 'green', 'blue'] 要求去除数组中重复的元素。
           1. 遍历数组
           2. 判断当前元素是否存在新数组
           3. 添加
       */
        var arr = ['blue', 'green', 'blue'];
        var newArr = new Array();

        for (var i = 0; i < arr.length; i++) {
            if (newArr.indexOf(arr[i]) == -1) {
                newArr.push(arr[i]);
            }
        }
        console.log(newArr);
    </script>
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